Bread slicing machine



LNov. 28, 1939. w, HOPPE 2,181,681

BREAD sLIcING MACHINE Filed July l5, 1938 4 Sheets-Sheet l Nov. 28,1939.w. Hoppa BREAD SLIGING MACHINE Filed July 13, 1938 4 Sheets-Sheet 2INVENToR Mum/v fop/2f BY M 9AM ATTORNEYS NOV. 28, 1939. w, HOPPE BREADsLICING MACHINE Filed July 13, 1938 4 Sheets-Sheet 3 INVW Mza/W 6P/of BYTToRNEYs knives.

Patented Nov. 28, 1939 UNlTED STATES @NEEMT GEMM?.

2,181,681 BREAD* SLICING MACHINE Application July 13, 1938, Serial No.218,992

20 Claims.

This invention relates to improvements in bread slicing machines. Oneobject of the invention is to provide a mode of synchronizing the feedof the loaves through the slicing mechanism with the speed of apusher-type delivery conveyor, this synchronization being preferablyautomatically controlled. A further object is to improve the manner ofmounting the slicing A further object is to provide improved mechanismin various parts of the machine. A further Objectis to provide animproved form of clutch by which the slicing mechanism may besynchronously connected to an associatedwrapping mechanism. Other andfurther objects will appear from the following description and claims.

This application is a continuation in part of my prior applicationSerial No. 125,371, filed February l2, 1937.

Referring to the drawings,

Fig. 1 is a side elevation of the machine, partly in longitudinalsection.

Fig. 2 is a section on line 2 2 of Fig. 1;

Fig. 3 is a section on line 3 3 of Fig. 1 with certain parts brokenaway.

Fig, 4 is a detail showing certain clutch mechanism;

Fig. 5 is a section on line 5 5 of Fig. 4, showing the clutch in fulllines in released position and in dotted lines in engaged position;

Fig. 6 shows the clutch in the process of releasing itself when thecontrol is shifted;

Fig. 7 is a section on line 'l-l of Fig. 4, with the parts shown in fulllines in released and in dotted lines in engaged position;

Fig. 8 is a section on line 8 8 of Fig. 4;

Fig. 9 is a section on line 9 9 of Fig. 4, showing the clutch. inreleased position;

Fig. 10 a detail of the knife mounting;

Fig. 11 is a detail of one of the knife holding springs;

Fig. 12 is a detail plan of one of the side guides adjacent thetermination of the delivery conveyor;

Fig. 13 is a detail plan of one of the side guides adjacent the entranceto the delivery conveyor;

Fig. 14 is a detail showing a method of releasably holding one oi" theloaf supporting plates;

Fig. l5 is a detail showing a control mechanism for augmenting the feedof the loaves during one cycle. showing the device inactivated by reasonoi the correct positioning of a loaf:

Fig. lo is a similar view showing the device activated by the incorrectpositioning of a loaf caused by insuflicient feeding speed;

Fig. 17is a similar view showing a device for ,in a crank case 34carried by the rails 22.

decreasing the feeding speed during one cycle when the loaves are beingfed too fast;

Fig. 18 is a detail of mechanism shown in Figs. 15 to 17;

Fig. 19 is a detail of mechanism for causing a permanent correction ofthe loaf feeding speed; and

Fig. 2D is a detail of certain electrical devices used with themechanism of Fig. 17.

' The slicing machine being centered around the reciprocating knifeframes the description will be started atV that point. The main frame20, upon which all of the mechanism is eventually supported, has crosspieces 2l at its end, to which longitudinal rails 22 are secured as bybolts 23. These rails form a combined track and subframe upon which' theknife operating mechanisms are carried and upon which they may be slidout at one end of the main frame after they have been disconnected. Uponthe rails four vertical bars 2li are secured as by bolts 25, carrying attheir upper ends pins 25 upon which the knife frames slide in a mannerto be described. The lower portion of each bar is reduced as at 21 sothat if expansion of the knife frames occurs due to the heat ofoperation, the bars may yield outwardly. This yielding will be conned tothe reduced portion of the bars so that their bearing portions will beleit straight since the expansion is small these bearing portions willremain substantially parallel. Screws 23 are threaded into the bars andheld by locknuts 29 in adjusted position so that their heads di? willstrike the frame 2@ and limit the outward movement of the bars Zfl,thereby securing centralization of the knife frames and avoidingsidewise oscillation while leaving suicient room for heat expansion.

The knife frames 3l are preferably made in rectangular form and ofhollow construction, and are provided with lugs 32 having a running iitupon the pins 2S. The lugs 32 are located welll toward the top oftheframes, so that a well distributed three-point support is obtained foreach frame; the lugs being separated. by the width of the frame fromeach other and by the full height of the frame fromthe other point of.support at the bottom. At their lower central points the frames aredetachably connected to the upper ends of rods 33 mounted for verticalyreciprocation The rods 33 are connected by links 35 with opposite endsci a rocker 36 carried on a pivot shaft 3l'. This shaft also carries anarm 38 joined by a link 3@ with a crank pin lll on a counterbalancingdisk 4i mounted on the end of a shaft 42 likewise mounted in the crankcase. At its outer end the shaft 42 carries a pulley 43 connected by abelt 44 with a motor 45. The pivot shaft 46 may be provided with acounterbalance 46 to prevent vibration.

The knives are mounted on their frames by a novel yielding mountingwhich holds the knives individually under tension. Along the lower crosspiece of each knife frame a bar 50 (Fig. 1) is removably dovetailed inplace, provided with bifurcated lugs 5| receiving the knives. Cross pins52 on the knives 53 prevent upward movement of the latter. The upperends of the knives are yieldably held as is best shown in Figs. l and10. A U-frame 54 is bolted at 55 to the upper cross piece of each knifeframe, the lower portion `of the U-frame being provided with a rib 56traversed by slots 51. Through each of these slots passes a spring 58having a knife-receiving bifur- (cation 59 at one end and a hole ordepression 80 fat the other. When the spring is inserted in the 'slotand engaged at its forked end by the cross pin 52 of a knife, it can betensioned by a screw 6| threaded through the U-frame and engaging thehole 60, which acts as a positioning means. The tension on the springcan be adjusted by means of the screw 6|, the latter being then securedby a lock nut 62. Thereafter the spring can be depressed to permit theknife to be removed without changing this adjustment by means of a lever63 engageable in a groove 54 in the knife frame and having a heel 65bearing on the spring as shown in dotted lines in Fig. 10.

The loaves are introduced upon an inclined plate 10 provided with sideguides 1|. From this plate the loaves pass onto a belt 12 traveling overa supporting plate 13 and mounted on pulleys 14 and 15 carried by shafts16 and 11 respectively. Shaft 11 is driven by mechanism to be describedbelow. Above the bel-t 12 is an upper belt 18 mounted on pulleys 19 and80, suitably journaled for free rotation in a frame 8| carried by abracket 82. This` bracket has a wedge-like enlargement 83 supported on atapped collar 84 having a nange 85 in engagement with the enlargement soas to prevent rotation of the collar. The collar is threaded onto ascrew 86 journaled in the frame and provided with a hand wheel 81 sothat the belt 18 can be adjusted in its vertical position. The bracket82 surrounds the screw 86 loosely, so that the belt 18 rests on theloaves with a pressure due only to the weight of the bracket and theparts carried by it. If a loaf is high or becomes tilted the bracket canbe forced up on the screw without exerting undue pressure on the loaf.The bracket is prevented from turning sideways by guide rods 88 (Fig.2). During their passage along the belt 12 the loaves are guided by sideguides 90 and, after they leave belt 18, by a top guide 9| carried bythe bracket 8|. As the loaves leave the belt they are received on aplate 92 supported on its ends by brackets 93 having curved portionsembracing slabbed-oif pins 94 carried by the bars 24. In the positionshown in Figs. 1 and 2 the brackets are locked on the pins, but ifrotated clockwise the lesser diameter of the slabbed-off pins: registerswith the openings in the bracket and the latter may be slipped off. Tohold the plate in its normal position bolts 95 are slidably mounted inthe bars 24, as shown in Fig. 14, so as to fit into holes in thebrackets 93. The bolts carry pins 96 (see also Fig. 2) extending throughbayonet slots 91 inthe bars and engaged by springs 98 to hold the boltsnormally in the holes in the bracket.

The plate 92 has fingers 99 (Fig. 1) extending between the knife blades,so that a substantially continuous loaf supporting surface is formedfrom the belt 12 through the knives. When it is desired to remove theknife frames the plate can be removed as described.

Above the plate 92 are side guides |00 (Fig. l) pivoted to adjustablebrackets |0| by headed pins |02 (Fig. 13) having springs |03 underneaththeir heads. The guides |00 also carry short dowels |04 adapted to enterholes in the bracket |0| when the guide is in its normal position. Whenthe knife frames are to be removed the guides can be tilted up out ofthe way by pressing them inwardly sufficiently to free the dowels fromtheir holes. Each guide preferably carriesra thin spring plate |05having a bent portion |06 operating to engage the end of they slicedloaf and prevent undesired motion thereof.

The loaves slide down the plate 92 onto a delivery plate |01 along whichthey are carried by conveyor mechanism to be described. The deliveryplate is mounted on an arm |08 pivoted on a shaft |09 and provided withan arcuate slot l0 through which passes-a bolt I By this means theelevation of the outer end of the delivery plate can be varied tocorrespond to that of the infeed of a wrapping machine to which theslicer is coupled. Posts ||2 on this arm receive rods ||3 and H4 whichare held inposition by set screws H5. Rods ||3 carry the brackets |0|previously referred to, while rods ||4 are secured to side guides ||6also fastened to the brackets. At their ends the side guides I6 areprovided (Fig. 12) with spring plates ||1 having hooked ends H8preventing excessive inward movement. These spring plates preventundesired overtravel of the loaves under the impetus given them by thedelivery conveyor.

Mounted on sprockets on shaft |09 and on an idle shaft |20 are sidechains |2| bearing pushers |22 which extend across the delivery plate|01, passing in the motion of the chains first upwardly through thespace between plates 92 and |01, then along plate |01, and nallyreturning underneath the latter plate. Shaft |09 is driven by a chain|23 passing over sprockets |24, |25, and |26. Sprocket |24 is on shaft|09; sprocket |25 (Figs. 1 and 4) is loosely mounted on a shaft |21preferably driven from the associated wrapping machine; and sprocket |26(Figs. l and 3) is loosely mounted on a stub shaft |28. The sprocket |25is driven from the shaft |21 through a clutch mechanism which stops thedelivery conveyor in a predetermined position and starts it in timedrelation to the wrapping machine. This clutch comprises a sleeve |30freely mounted on v the shaft and pressed towards the left in Fig. 4

by a spring |3| acting against a collar |32 pinned to the shaft. Aclutch bar |33 attached to the sleeve extends through a slot |34 in amember |35 pinned to the shaft; and, if the sleeve is displaced to theleft from the position shown in Fig. 4, extends into a slot |36 in amember |31 secured to the sprocket |25. The latter slot is made somewhatwider than the clutch bar in order to facilitate its engagement.

The sleeve |30 carries a cam member |40 having an axially inclinedradial surface |4| at the bottom of which is a spiral ledge |42.Disposed a short distance radially within the inner terminus of thespiral ledge is a circumferential ledge |43. A cam roll |44 is pivotedat the end of an arm secured against axial movement but free to rotateupon a shaft |46 extending transversely of the machine. Fixed tothisshaft is a collar |41, serving to prevent axial movement of the armin one direction and having a notch |63 one side of which under certainconditions may engage a pin 49 on the arm so as to rock the arm into thedotted line position of Fig. 7. A spring l@ urges the arm in thecontrary direction. The shaft |46 is rocked by ahandle |5l and is heldin either of two positions by a pin |52 (Figs. 4 and 9) pressed by aspring |53, recessed in an arm |54 xed to the shaft, into one of twodepressions |55 in a plate secured to the frame.

The clutch is shown in Fig. 5 as in disengaged position. If the handlell is rocked to the right in Fig. 7 the edge of notch |58 will be movedagainst the pin |49, and the arm will be lifted into the dotted linepositio-n of Fig. 5, permitting spring l3| to move the bar |33 into thenotch |36 as soon as it comes into registry. The roll is held completelyout of contact with the cam Mil during continued operation of themachine. It should be noted that since the shaft |21 is driven from thewrapping :machine the parts driven by sprocket i125, notably thedelivery conveyor, will always be operated in timed relation with thatmachine.

To clisengage the clutch the handle l5| is rocked to the position ofFig. 6, moving the side of notch all away from the pin |49 and permituting spring i5@ to move the roll Hill towards the of shaft |21. If thisoccurs while the cylindrical part'of the cam lili) is underneath theroll the cam will turn under the roll without effect until the cut-awaypart is encountered. As soon as this occurs the roll will be permittedto move inwardly by the spiral vcam |42 and at the same time the sleeveliil will be forced to the right in Fig. l by the pressure of theaxially inclined surface Ml against the axially stationary roll Hifi. Assoon as the end of this inclined surface passes the roll the latterrests against the plane end of the cam, and will be pulled inwardllr bythe spring ll'ail until it rests against the ledge llll. Continuedrotation finds the roll pressed against the shoulder formed between thisledge the inner terminus of the spiral surface |42; so that the sleeve|30, which rotates constantly with the wrapping machine, finds noresistance offered by the roll and the cut-away portion |t| produces noeffect. The bar 533 will be pulled out of the notch |36 by the axialmovement of the sleeve in a predetermined angular position, so chosenthat the parts will be stopped in about the position of Fig. l, with one.of the pushers |22 just below its' point of emergence between theplates and lill'. This permits loaves of bread which have been stoppedin the knives to be cleared from the machine by pushing them throughmanually with another loaf without interference from the pushers. At thesame time it will be noted that the pusher |22 at the right in haspassed around the end of the delivery plate, thus having completelydelivered a loaf to the cross feed of the wrapping machine. Were a loafto be arrested half on the plate |131 and half on the wrapping machinefeed it would be mashed by the continued operation of the latter, acondition avoided by the construction disclosed; A further advantage isthat when the delivery con-v veyor is stopped no pusher will be in aposition to interfere with the removal of plate 92.

The shaft lflt is preferably provided with an arm l (Fig. connected by alink |51 with an arm |58 secured to a shaft 559 which may be providedwith a handle |60 (Fig. 3) for convenience in operating the clutch fromthe yother end of the machine. An abutment |5| may be arranged on thearm |58 in position to contact an arm |62 extending from the startingswitch |63 of motor 45, so that the feed of loaves cannot be startedwithout starting the slicing motor, a

Acondition which would result in jamming and possible breakage.

The feed belt 'l2 is driven by a variable speed device which can beadjusted in accordance with the width of the loaf to be sliced so thatone loaf will be delivered on. each passage of the delivery pushers 22.The drive shaft 11 of this feed belt is connected by a chain |65 with astub shaft |65 bearing a large pulley t1. A belt |63 encircles thispulley and also an idle pulley |69, and passes between a pair of conepulleys |10 (Fig. 3) mounted on the shaft S23 and pressed together byspring lll. One of the pulleys is connected to the sprocket 26previously mentioned so as to be driven thereby. The pulley |59 acts toregulate the degree te which the belt is drawn between the cone pulleysand thus acts to regulate the speed of the feed belts. To this end thepulley |69 is mounted on a lever |12 pivoted at |13 to the frame andjoined by a link |14 to a rocker |15 pivoted to the frame at |16. Therocker is also i connected by a link |11 to a traveler |18 threaded to ashaft |19 journaled in the frame and having hand wheels ltl at its endby which the position of roller it be varied through the linkagedescribed.

It is desirable to have some manner of setting the machine to theapproximately correct feeding speed before starting it. For this purposethe traveler |18 has an arm i8! extending through a slot E82 in theframe and bent over at its free end so as to act as an abutment for oneside of a test loaf. A fixed abutment |83 is provided for the other sideof the loaf.. In adjusting the machine a loaf of the size to be yslicedis held against the abutment i533, as indicated in dotted lines in Fig.3, and the arm ll adjusted by rotating the hand wheels l@ to contact theother side of the loaf. The proportions of the linkages and pulleysdescribed are so chosen that the pulley |69 will be shifted by thissetting to give to the feed belt the approximate correct speed for thatsize of loaf. As loaves are not constant lin size some adjustment may benecessary while the machine is running, matter easily taken care of byrotating the hand Wheels 80.

Even with an initially accurate setting of the feed belt speed,variation in loaf size will cause the loaves to vary somewhat in the'timed relation in which they are delivered to the pushers |22. It isparticularly undesirable that the loaves be fed fast enough so that twoloaves Will be placed between. adjacent delivery pushers, and in theendeavor to avoid this the feed is frequently kept suiiiciently slow sothat a loaf may not be fully cn the delivery platform by the time apusher rises above it. This results' in the rear of the loaf riding on apusher in the manner indicated in Fig. 16. plication Serial No. 125,371,mechanism is preferably provided to move such a loaf ahead of the pusherso that it will be seated at on the delivery table. In the present casesuch mechanism consists cf a bail E85 extending across the path of theloaves and carried by a rocker 586 journaled in standards |31. Therocker is connected by a link i3d to an arm |89 pivoted to the frame at|993 and bearing a cam roll |9|. Asp-ring |32 acts As described in myprior ap-r :with the sprocket |25.

on the lever to hold the roll against a cam |93 connected to thesprocket |25. The bail is given a rearward swing high enough to`c1ear aloaf passing under it, and is then swung forwardly far y enough tostrike the rear of a loaf and move it just in front of the pusher sothat it is seated squarely upon the delivery plate.

If the speed is so slow that the loaf overhangs the pusher aconsiderable amount, the bail may strike the top of the loaf and crushit, or if the spring |92 is lightened sufficiently to prevent this theloaf may not be moved. it is, therefore, desirable in some cases toreplace or supplement the manual control with automatic mechanism toregulate the speed so that the feed belt isspeeded up whenever a loafrides on the top of a pusher, thus avoiding the cumulative tendencywhich would otherwise cause the loaves to lag progressively greater andgreater amounts. The correction is conveniently applied to the pulley'l5 which drives the feed belts. For this purpose. the pulley l5 isdriven from the shaft il by any conventional free wheeling clutch (notshown) which drives the pulley positively at the speed of the shaft 'butpermits the pulley to be moved ahead of the shaft when desired by othermechanism. A ratchet i95, preferab-ly having underout teeth for apurpose to be described, is secured to the pulley. An arm |96 is freelypivoted on the shaft and is coupled by a link |97 to an arm |92 pivotedto the frame at |99 and bearing a cam roll 233. The arm is drawn to holdthis roll against a cam 23| by a spring 262. Cam 232 ispreferably-secured to the cam 93, and rotates A pawl 263 is pivoted toarm |93 at 225 (Fig. 18), and isdrawn away from the ratchet by theweight of its tail ZB or 'by a suitable spring. Also freely pivoted uponthe shaft 'il is an arm 2id having an abutment a, 2li adapted to contactwith the tail 226 of the pawl. when the arm is held by a spring 2|2 inwhat might be called its normal position. The end of the arm 2i() isformed with a hook 2|3 which is adapted to be engaged by either of tworetainers 2| l and 2|5, which are pivoted at 2|5 and 2H respectively tostationary brackets 2|8 and 2|9. Retainer 2|@ is normally held in theinactive position of Fig. by a spring 223; while retainer 2|54 isnormally held by its spring 22| in the position shown in Figs. l5 and 16in which its end will engage the hook 2|3.

The arm i9@ is oscillated continually about the shaft il, the pawl 2533being normally held out of contact with the ratchet by the pressure of:arm 2id against it as shown in Fig. 15. If one of the retainersrestrains the arm 2|| from following the arm |96, as in Fig. 18, thespring 2|2 is stretched and the pawl 233 moves away from the arm 2H),turning into contact with the ,iratchet and causing it to rotate. Oncein engagement with the ratchet, the undercut teeth of the latterYprevent its disengagement until the arm 96 slows down to a speed lessthan the ratchet.

During the major part of the clockwise oscillation of the pawl it ismoving at an angular speed highretainer .2M by a magnet 222, and theretainer 2i5 by a magnet 223. When the magnet 222 is activated the arm2H) will be held from following the pawl throughout the whole of theclockwise oscillation of the pawl, and the ratchet will therefore begiven its maximum supplementary advance. If the magnet 223 is activatedinstead, the arm 2|@ will be engaged by neither of the retainers and itwill travel throughout the stroke of the arm |95 in constant engagementwith the pawl. The pawl will, therefore, be held out of engagement withthe ratchet and no supplementary motion will be given to the pulley. Theconstant speed given to the pulley is chosen in this modication so as togive a slight` underfeed to the loaves and the effect will be totemporarily reduce the normal feed of the loaves. If neither magnet isenergized the arm 2li) will travel in contact with the pawl until it isheld by the second retainer 2i5, whereupon the pawl will be permitted toengage the ratchet. A supplementary advance half of its maximum will begiven to the pulley in this way, the constant speed of the ratchet beingchosen so that the basic advance given to the loaf feeding conveyor bythe combined action will be the correct amount necessary to feed theloaves in correct registration with the delivery conveyor.

Magnet 222 is connected by a wire 225 with a contact 223 carried by apivoted detector 22'l normally held by a spring 228 in the elevatedposition of Fig. 16. Another contactor 22S is fixed in position, and isconnected by a wire 233 with a stationary contactor 23|. A movablecontactor 232 is carried by a detector 233 normally held by a spring 234in the dotted line position of Fig. l5. This latter contactor 232 isconnected by a wire 235 through a current source 236 with a brush 237 incontact with the surface of an insulating disk 238 on the shaft |93. Asecond brush 239 also in contact with the disk is connected by a wire246 with the magnet 222. A conducting strip2l| on the disk is ofsuihcient length to bridge the two brushes once during each cycle, at atime when the detecting action is desired, and thus prevents theenergizing of the magnet at any time other than when a loaf is supposedto Ibe over .the detector 227. The detector 233 serves a somewhatsimilar purpose, being lowered to prevent closing of the circuit exceptwhen a loaf is in position under it, and thus to prevent activation ofthe magnet and consequent disruption of the'timing of the feedingmechanism during periods when no bread is being fed through the machine.

In Fig. l5 a loaf is shown as being fed in normal position, seatedsquarely in front of one of the pushers on the conveyor. .The detector221 is held down by the loaf and no correction in the feedis caused.rfhe detector will spring up as soon as the pusher has passed over it,but no activation of the magnet will be caused since the vconductingstrip 24| will by this time have passed beyond the position where itvcontacts both brushes. In Fig. 16 a loaf is shown as having been fed tothe conveyor somewhat late, so that it is riding on one of the pushers.There is thus a space left underneath the loaf, into which thedetector'moves. The circuit will therefore be closed, the magnet 222energized,l and the arm 2 l@ will be held back to permit the pawl togive a slight excess feed to the feed pulley, causing subsequent loavesto be advanced in relation to the delivery conveyor.

The mechanism described will serve to ,correct mechanism as a whole.

a delay in the feeding of the loaves, but since a loaf fed too far aheadwill rest on the delivery. plate until a pusher catches up with it nodifference in position can be detected by the time it reaches theposition of Fig. 15. To detect advance feed of the loaves it isnecessary to locate a detecting mechanism at a point before the contactof the pusher with the loaves. A mechanical detector may be used as inthe preceding case, but it is somewhat more convenient to employ aphotoelectric cell, which might also be substituted for the mechanicaldetector 221.

A light source 242 (Fig. 20) is arranged at one side of the path of theloaves and a photoelectric cell 243 at the other in position to detect abeam of light from the light source through a slot 244 (Fig. 17) in adisk 245 secured to the shaft of the delivery conveyor. Suchphotoelectric cellsl are standard commercial products, together with theamplifiers which are controlled by them and which serve to build uptheir feeble currents to a strength sufficient to operate a magnet. Thedetails of cell and amplifier are therefore not illustrated, it beingsuflicient to indicate that the amplifier 2li@ is connected by wires tothe electromagnet The disk M5 serves the same purpose as the disk 232ipreviously described, preventing the actuation cf the magnet except incorrect timing with the If a loaf is fed too far in advance, as in Fig,i7, it will be out of the path of a light ray coming through the slot2M; the preceding loaf being still in a slanting position on plate andhence leaving a il-shaped opening between the two loaves through whichthe light can pass. The light is received by the photo cell and theresulting activation of the magnet 223 serves in the manner described todecrease the feed of the loaves. If a loaf is in proper position it willblock the light rays, and no activation of the magnet results.

The correcting mechanism thus far described changes the feed for onecycle only, leaving the normal feed rate unchanged. It is preferable tocombine this with the mechanism about to be described, by which thenormal feed rate will be varied with each correction, but to a muchsmaller degree, so that the mechanism will tend to stabilize itself andeliminate the need of frequent correction. A mechanism for this purposeis shown in Fig. i9, operating on the pulley los and changing itsposition to change the normal feed given to the pulley l5. Thiscomprises two arms 250 and 35i mounted to oscillate upon the shaft H3.Arm 25d is oscillated by a link 252 extending from an eccentric 253 onshaft i2?, and arm 25l has an extension 256i connected by a link 255with an eccentric Ei. The eccentrics are set in opposition, so that theycscillate the arms in opposite directions at the same time. Arm 25Bbears a pawl 25? and arm 25l a pawl 253, each being held normallyinactive position by a spring 259. A ratchet 2&6, having double facedteeth, is mounted on a sleeve 26S on the shaft. The sleeve carries aspiral gear 232 meshing with a spiral gear 263 on a shaft 2M held forrotation but against longitudinal movement in an abutment 255 by collars256. The shaft is threaded at 261 and runs in a nut 266 formed on an arm26s fast on the arm |12 which carries the pulley 69. Magnets 2H and 2'l2are mounted adjacent the path 0f the pawls, activation of either onecausing its paWl to be brought into contact with the ratchet just afterthe pawl has started its oscillation, the pawl maintaining itself incontact with the ratchet until the pawl starts its return stroke. Onemagnet is connected in the circuit of magnet 222, and the other in thecircuit of magnet 223, so that when correction in either direction iscalled for a slight adjustment of pulley |59 will be made in a directionwhich will tend to reduce the necessity for further correction in thesame sense.

I claim:

l. A knife mounting for bread slicing machines comprising asubstantially rectangular frame, means on one side of the frame forremovably securing one end of each of a plurality of knives thereto, amember having a plurality of spaced apertures located at the other sideof the frame, a plurality of fiat springs each extending through one ofthe apertures and having at one end means for interengagement with aknife, and adjustable set screws carried by the frame for exertingknifetensioning pressure on the other end of each of the springs.

2. A knife mounting for bread slicing machines comprising asubstantially rectangular frame, means on one side of the frame forremovably securing one end of a plurality of knives thereto, a pluralityof fiat spring rockers each held intermediate their length in theopposite side of the frame and having at one end means forinterengagement with a knife, adjustable members carried by the framefor exerting knife-tensioning pressure on the other end of each of thesprings, and a ledge adjacent one end of the springs for permitting theflexing of the spring by a pry-bar,

3. In a bread slicing machine having a frame, a plurality of spacedknives, and means for conveying loaves to and away from the knives; aplate having fingers extending between the knives to support the loaveswhile being sliced, end brackets carrying the plate and each havingadjacent its lower end a laterally open slot with a narrowed opening,pins carried on the frame in position to be received by each of saidslots, the pins being slabbed off so as to permit the slotted bracketsto pass over them when the plate is tilted but to hold the bracketsfirmly when the plate is in normal position, and means for releasablyholding the upper portions of the brackets to the frame when the plateis in normal position.

fi. In a bread slicing machine of the type having slicing mechanism,means for feeding loaves through the slicing mechanism, and apushercarrying delivery conveyor driven independently of the slicingmechanism; mechanism for controlling the timing of the delivery conveyorwith respect to the wrapping or other machine to which the deliveryconveyor delivers the sliced loaves comprising a drive shaft driven fromsaid wrapping or other machine, a notched sleeve freely rotatable on thedrive shaft and coupled to the delivery conveyor, a sleeve splined tothe drive shaft for slidable motion thereon, a dog carried by thesplined sleeve and engageable by sliding movement thereof with the notchon the first named sleeve, a spring pressing the splined sleeve in adirection to cause engagement of the dog with the notch, a cam diskcarried by the splined sleeve and having a cam surface inclined in thedirection of the axis of the shaft, a cam roll, and a mountfor the camroll restricting it from motion laxially of the shaft but permitting itto be moved .radially thereof into engagement with said axially inclinedcam surface.

5. In a bread slicing machine of the type having slicing mechanism,means for feeding loaves through the slicing mechanism, and apushercarrying delivery conveyor driven independently of the slicingmechanism; mechanism for controiling the timing of the delivery conveyorwith respect to the Wrapping or other machine to Which the deliveryconveyor delivers the sliced loaves comprising a drive shaft driven fromsaid wrapping or other machine, a notchedsleeve freely rotatable on thedrive shaft and coupled to the delivery conveyor, a sleeve splined tothe drive shaft for slidable motion thereon, a dog carried by thesplined sleeve and engageable by Sliding movement thereof with the notchon the first named sleeve, a spring pressing the splined sleeve in adirection to cause engagement of the dog with the notch, a cam diskcarried by the splined sleeve and having a cam surface inclined in thedirectiton of the axis of the shaft, a spiral cam surface, and acircumferential shoulder to Which said axially inclined and spiral camsurfaces both lead, a cam roll, and a mounting for the cam rollrestricting it from motion axially of the shaft but permitting it to bemoved radially thereof into engagement with said axially inclined camsurface.

5. A bread slicing machine having slicing knives, means for driving theslicing knives, a pusher-carrying delivery conveyor, a loaf feedingconveyor frictionally engaging the loaves to feed them in an unbrokenseries to and through the knives, a drive shaft for said loaf feedingconveyor, a power shaft driven independently of said slicing knives andin timed relation with said delivery conveyor, a pulley on one of saidshafts and a pair of spring pressed cone pulleys on the other of saidshafts, an idler pulley, a belt surrounding said pulley, cone pulleys,and idler pulley, and means for adjusting the position of the idlerpulley.

7. A bread slicing machine having slicing knives, means for driving theslicing knives, a pusher-carrying delivery conveyor, a loaf feedingconveyor frictionally engaging the loaves to feed them in an unbrokenseries to and through the knives, a drive shaft for said loaf-feedingconveyor, a power shaft driven independently of said slicing knives andin timed relation with said delivery conveyor, a pulley on one of saidshafts and a pair of spring pressed cone pulleys on the other of saidshafts, an idler pulley, a belt surrounding said pulley, cone pulleys,and idler pulley, a linkage for adjusting the position of the idlerpulley, a fixed abutment in an exposed position on the frame, a movableabutment connected to sai-d linkage in position to receive a test loafbetween it and the fixed abutment, said linkage being so proportionedthat when said abutments are spaced apart a distance equal to thethickness of the test loaf the idler pulley Will be set to give a speedto the loaf feeding conveyor which will deliver one sliced loaf to eachpusher of the delivery conveyor.

8. In a bread slicing machine, slicing knives, a continuously movingconveyor operating to forward by frictional contact an unbroken seriesof loaves to and through the knives, a continuously moving conveyorhaving spaced flights carrying the sliced loaves away from the knives,manually controlled means for varying the speed of the first namedconveyor relative to the second to cause the delivery of one loaf foreach of said flights, and loaf calipering means connected to saidmanually controlled means to indicate an initially approximately correctsetting of said latter means for a loaf of a particular size.

9. In a bread slicing machine, slicing knives, continuously operatingmeans for feeding loaves to the knives, means for removing sliced loavesfrom the knives at periodic intervals, means for detectingmisregistration of a sliced loaf with respect to the delivery means, aspeed variator for driving the feeding means, and mechanism controlledby said detecting means and connected to the speed variator to vary thespeed of the loaf feeding means during its continued movement.

10. In a bread slicing machine, slicing knives, means for continuouslyfeeding loaves to the knives, means for removing sliced loaves from theknives at periodic intervals, means for detecting a lagging relation ofa sliced loaf with respect to the delivery means, and mechanismcontrolled by said detecting means for accelerating thecontinuouslyoperated loaf feeding means,

11. In a bread slicing machine, slicing knives, means for feeding loavesto the knives on a downward slant, a downwardly inclined plate receivingsliced loaves from the knives, a substantially horizontal deliveryconveyor having spaced flights in position to receive sliced loaves fromsaid plate, means for detecting the presence of a loaf partially ridingon one of said flights, means for accelerating the loaf feeding means,and connections between the detecting means and said accelerating meansto cause acceleration thereof when a loaf is in a lagging position.

l2. A bread slicing mechanism comprising slicing knives, a continuouslymoving loaf feeding conveyor positioned to feed loaves to and throughthe knives, a pusher-carrying conveyor positioned ,to receive slicedloaves pushed through the knives by the feeding conveyor, a loafdetector positioned to detect abnormal positioning of a loaf relative tothe delivery conveyor, means for varying the speed of operation of thefeeding conveyor, and operating connections between the detector andsaid speed varying means.

13. A bread slicing machine comprising slicing knives, a loaf feedingconveyor positioned to feed loaves in an unbroken series to and throughthe knives, a pusher-carrying conveyor positioned to receive slicedloaves pushed through the knives by the feeding conveyor, a loafdetector positioned to detect an abnormal lag of a loaf relative to thepushers of the delivery conveyor, means for driving the loaf feedingconveyor a normal amount at each machine cycle, means for causingtemporary excess feed of the loaf feeding conveyor, and connectionsbetween the detector and the last named means to permit actuation ofsaid last named means only when a loaf is in lagging position.

14. A bread slicing machine comprising slicing knives, a loaf feedingconveyor positioned to feed loaves in an unbroken series to and throughthe knives, a pusher-carrying conveyor positioned to receive slicedloaves pushed through the knives by the feeding conveyor, a loafdetector positioned to detect abnormal advance of a loaf relative to thepushers of the delivery conveyor, means for driving the loaf feedingconveyor a basic amount at each machine cycle, means for causingtemporarily diminished feed of the loaf feeding conveyor, andconnections between the detector and the last named means to permitactuation of said last named means to diminish the feed only when a loafis in abnormally advanced position.

l5. A bread slicing machine comprising slicing knives, a loaf feedingconveyor positioned to feed loaves in an unbroken series to and throughthe knives, a pusher-carrying conveyor positioned to receive slicedloaves pushed through the knives by the feeding conveyor, a loafdetector positioned to detect an abnormal lag of a loaf relative to thepushers of the delivery conveyor, a loaf detector positioned to detectabnormal advance of a loaf relative to the pushers of the deliveryconveyor, means for driving the loaf feeding conveyor a basic amount ateach machine cycle, speed varying means for alternatively increasing orretarding the speed of the loaf feeding conveyor, and means controlledby said two detectors for activating said speed varying means toincrease the speed of the loaf feeding conveyor if a loaf has anabnormal lag or to decrease its speed if a loaf has an abnormal advance.

i6. In a bread slicing machine of the type having slicing knives, a loaffeeding conveyor positioned to feed loaves in an unbroken series to and'through the knives, means for driving the feeding conveyor at a basicspeed, and a pusher-carrying conveyor positioned to receive slicedloaves pushed through the knives by the feeding conveyor; thecombination with said elements of detecting mechanism for detectingabnormal lag or advance of a loaf, means controlled by said detectingmechanism for augmenting or decreasing the movement of the conveyor adefinite amount each time a loaf is abnormally lagging or advanced, andmeans controlled by said detecting mechanism to decrease the basic speedof the loaf feeding conveyor when a loaf is abnormally advanced and toaugment said basic speed when a loaf is abnormally lagging, said changesin the basic speed being of a magnitude to produce a change in themovement of the loaf feeding conveyor at each substantially less thanthe change produced by said first named detector controlled means.

i7. In a bread slicing machine, slicing knives, means for pushing anabutting series of loaves through the knives, an endless series ofpushers mounted for movement adjacent said knives to'engage the rear ofthe leading loaf of said abutting series and to carry it away from theknives, said pushers being driven at a rate of speed sufficient toforward at least as many loaves per unit of time as are fed through theknives by the first named pushing means and being of sufficiently lowheight to permit a pusher to ride under a loaf and carry the loaf alongin a tilted position in case the leading loaf of the series is notsuiciently advanced to permit the pusher to contact its rear face, and apusher movable in timed relation to said pushers but at a higher `rateof speed to engage the rear face of said tilted loaf and move itforwardly oif from its pusher and to a position in front of the latter.

18. In a bread slicing machine, slicing knives,

means for pushing an abutting series of loaves through the knives, anendless series of pushers each mounted `for movement adjacent saidknives to engage the rear of the leading loaf of said abutting seriesand to carry it away from the knives, said pushers being driven at arate of speed sufi"- cient to forward at least as many loaves per unitof time as are fed through the knives by the first named pushing meansand being of sufficiently low height to permit a pusher to ride under aloaf and carry the loaf along in a tilted position in case the leadingloaf of the series is not suiciently advanced to permit the pusher tocontact its rear face, an oscillatory pusher mounted for movementbetween a retracted position clear of the path of the loaves and anadvanced position intersecting the path of the loaves, and mechanism forholding said oscillatory pusher in its retracted position to permit thepassage of each successive loaf and for moving it from its retracted toits advanced position at a speed greater than the speed of said pushersto engage the rear face of a tilted loaf and move it forwardly off fromits pusher and to a position in front of the latter.v

19. In a bread slicing machine, slicing knives, means for feeding loavescontinuously to the knives, means for removing sliced loaves from theknives at periodic intervals, means for detecting misregistration of asliced loaf with respect to the delivery means, mechanism controlled bysaid detecting means for accelerating the speed of the continuouslyoperating loaf feeding means, and a pusher contacting the rear of theloaf to forward it sufficiently to overcome its misregistration.

20. A knife frame mounting for bread slicing machines of thereciprocating saw type comprising a main frame, knife frames, a pair ofspaced vertical bars of substantially greater length than the height ofthe knife frames, means rigidly securing the bars at their lower endsonly to said frame whereby their upper portions are free to movelaterally, intertting connections between the upper part of the bars andthe upper part of the knife frames to permit slidable movement of theknife frames, and means coupled to the lower part of the knife framesfor reciprocating the frames, the said vertical bars having adjacenttheir lower ends, and above said securing means, localized portions of athickness sufficiently reduced with respect to the body of the bars topermit the expansion of the knife frames by the heat of operation to eXthe bars laterally without excessive pressure on the knife frames.

WILLIAM HOPPE.

